Hiya brother fork, and welcome to the Monastery   8^)

I did a quick search for 'install module' in the search form at the upper left, and turned up hundreds of hits to nodes that might help you out.   As a completely fair an unbiased observer, my two favorites are "A Guide to Installing Modules" and "difficulty using CPAN.pm".

Would you give them a read, and let us know what (if any) problems you encounter?   No shortage of smart+friendly monks here if you do encounter snags.   Of course, this all assumes that what you want to do is install the Tk CPAN module.
    cheers,
    Don
    striving toward Perl Adept
    (it's pronounced "why-bick")